David Deng, owner of the 3-month-old Terra Cotta Warrior, says it has taken him five years to open a restaurant serving the food of central China's Shaanxi province. His challenge: Most people outside China have never heard of it.

Yet by the time it opened in March, Terra Cotta Warrior was the second Shaanxi restaurant to open in San Francisco in just eight months. The city, it seems, is finally ready for Xi An Gourmet's and Terra Cotta Warrior's hand-made noodles, lamb stews and Chinese burgers.

Tall and slim, with the look of a man who keeps his wit tucked away but at close reach, Deng was born in Qishan, a small city 35 miles west of Xi'an, Shaanxi's capital.

He arrived in San Francisco 17 years ago. Though he had trained as a photographer, his English wasn't good enough to practice his trade. Like so many other new immigrants, he joined a kitchen brigade instead.

As Deng's language skills and finances improved, he opened a series of restaurants: first Wild Pepper in Noe Valley, then Crazy Pepper near Balboa Park.

Hunt for right chef

Yet the American Chinese food they served - General Tso's chicken, sweet and sour pork - left him dispirited. At one point he returned to China for six months to travel around his home state, gathering recipes as well as photos and paintings to decorate the walls of his apartment. He cooked Shaanxi dishes for his friends. He hunted stateside for years for a chef who could capture the flavors he loved.

Finally, he found one in Los Angeles. In December, they located a space on Judah and 30th Avenue. Deng painted the walls mauve, installed burnished wood counters and tables, hung bare branches from the ceiling and covered the walls with the pictures he had brought back from China.

Deng didn't just have something to prove to Americans, but to his fellow Chinese immigrants as well.

"A long time ago, I worked in a (Chinese) restaurant, and the chef asked me, 'Where do you come from?' " Deng recounts. "When I told him Shaanxi, he said that everybody in Shaanxi was poor. I tell him it's not true. Actually, Shaanxi is rich and beautiful."

If you look at a map of China as if the country were a Paleolithic drawing of a horse, Shaanxi would be draped over its heart. That central location has given the region its historical significance. Governments from the Qin to the Tang dynasties maintained Xi'an as their capital, and it was the starting point of the northern branch of the Silk Road.

Carolyn Phillips, a Chinese food expert in Los Altos who blogs as MadameHuang.com and is writing "All Under Heaven," a survey of regional Chinese cuisines (scheduled for April 2015), says that cosmopolitan Xi'an has long incorporated flavors from all over the country.

Street vs. palace food

Still, says Phillips, what little Shaanxi food has made it to the U.S. isn't the city's renowned dumpling banquets. "It's not the refined palace food of yore; it's what people eat nowadays," she says. "These are dishes you would eat on the sidewalk or in homes."

Some of those iconic dishes are on the menu at Xi An Gourmet in the Inner Richmond. Formerly San Dong House, it was rebranded last year after a Shaanxi-born chef was hired.

Xi An Gourmet's Shaanxi fare is hidden amid dozens of generic Northern Chinese dishes on the menu. And at House of Xi'an Dumpling, a new restaurant in Chinatown that specializes almost entirely in Shandong-style noodles and dumplings, traditional Shaanxi dishes aren't even available.

One of the regional specialties that Xi An Gourmet makes particularly well: Shaanxi's renowned yang rou pao mo, a rich lamb stew filled with pasta cubes; an alternate version is served with wheat buns that diners tear up and soak in the broth (see the accompanying recipe).

The restaurant also makes rou jia mo, or "Chinese burger," a CD-size flatbread stuffed with Middle Eastern-tasting cumin lamb and a plethora of jalapeños, testament to the Muslim influence on Shaanxi cuisine.

As these dishes demonstrate, Shaanxi residents are not big rice eaters. Which means that at Terra Cotta Warrior, noodles and flatbreads dominate most tables.

For Deng, what defines Shaanxi cuisine even more than the wheat-versus-rice divide is the distinctive blend of spicy and sour flavors.

The food is not as potently tart as Dongbei (northeastern) food, he says, and not as saturated with chile oil as Sichuan cuisine. Explained in terms of Chinese medicine, the warming effects of the seasoning, as well as its many beef and lamb dishes, make Shaanxi food ideal for cool, foggy San Francisco.

Terra Cotta Warrior's lamb stew with bread is a more delicate than at Xi An Gourmet. Deng pays homage to his hometown with the splendid Qishan minced pork noodles, chewy lengths of hand-pulled pasta covered with a lightly vinegared pork broth and capped with chile oil.

The chef makes the deceptively simple "noodles with sizzling oil" (known in Mandarin as biang biang mian) by slapping flat, belt-wide noodles against a table as he stretches the dough; then he rips each length in half. The noodles are simply seasoned with black vinegar and chile flakes whose aroma is awakened with a douse of boiling oil.

You may have to doctor the noodles with the condiments on the table. A few dashes of soy or Deng's vinegar blend brings their flavor to life; if you want the food even spicier, he recommends adding a spoonful of the toasted chile and sesame paste he makes in-house.

Shaanxi heads west

Deng isn't the first American restaurateur to delve so deeply into Shaanxi food. In New York, Jason Wang has turned Xi'an Famous Foods, his father's tiny Queens stall, into a citywide phenomenon, and your average NYU student is now as aware as Beijing transplants of the restaurant's lamb-face salad and cumin-lamb burgers. Shaanxi restaurants can also be found in San Gabriel Valley, California's mecca for all foods Chinese.

But in Cantonese-dominated San Francisco, says Deng, the newer, spicier foods introduced by Northern Chinese immigrants have been a harder sell. In the weeks leading up to Terra Cotta Warrior's March 2 opening, he prepared his chef for some quiet months.

One week later, the restaurant sold out of noodles and breads by 11 a.m. The average age of the customers who gathered in the doorway to wait for tables and point smartphone cameras at their plates was 25.

"They're international students," he marvels. "Ninety-nine percent of my (Chinese) customers speak Mandarin, Shanghainese or Shaanxinese," he says, referring to northern dialects. Locals, bloggers and travelers from China have all since found the place, too.

Deng is clearly delighted that the city is falling for Shaanxi food.

"If you open this kind of restaurant 10 years ago, it would have gotten no business," he says. "I guarantee it."

Lamb soup with bread (yang rou pao mo): This hearty stew contains either cubes of dough or comes with bread to tear up and add to the broth (see accompanying recipe).

Lamb Soup With Biscuits

Serves 4 as a main dish

This recipe is adapted from Carolyn Phillips, whose cookbook, "All Under Heaven," (McSweeney's) will be published in April 2015. The meat and soup can be prepared ahead of time and refrigerated or frozen. As with most soups, it is better the next day. Any fat can be removed before the soup is reheated.

Instructions: If needed, cut the meat into 1-inch cubes. Place them in a medium saucepan, cover with water and bring to a hard simmer. Simmer the meat for about 10 minutes. Dump out the water and the scum and rinse the meat in a colander. Place the meat and the stock into a large pot.

Place the fennel seed and Sichuan peppercorns in a tea ball or tie in a piece of cheesecloth. Add the spice ball to the pot, along with the star anise, cinnamon, ginger, green onion, salt and chiles, if using. Bring the stock to a boil, reduce to a gentle simmer, and cook the lamb, uncovered, until tender, about 1 1/2 hours. Taste the lamb and soup and adjust the seasoning. If made ahead, cover and refrigerate or freeze.

To finish: Soak the wood ear mushrooms in hot water at least 1 hour; drain and cut into thin slivers, discarding any tough portions. If using cloud ear fungus, rehydrated in warm water for 30 minutes; drain and set aside.

Soak the bundle of cellophane noodles in cool water at least 30 minutes; drain, cut in half and reserve half of the bundle for another use.

Add the fungus and the noodles to the soup; simmer until the noodles are translucent, 5-10 minutes.

Serve the soup steaming hot, with cilantro, pickled garlic, vinegar and chili sauce for diners to add to taste. Accompany with the biscuits, which can be torn into the soup or dunked into the soup and eaten out of hand.

Chinese Biscuits

Makes 6

You can make the biscuits as the lamb soup is cooking if you are serving the soup the same day. Otherwise, these hardtack biscuits can be made a day ahead. If you want to keep them softer, store them in a zip-top bag.

1 1/3 cups + 2 tablespoons all-purpose flour

2/3 cup + 1 tablespoon pastry flour

2/3 cup cool water

1 teaspoon instant or rapid-rise dried yeast

Instructions: Sift the flours together, then place 1/4 cup in a medium bowl. Stir in the water and yeast, cover the bowl with plastic wrap and let sit at room temperature for about 1 hour, until the mixture is bubbly.

Stir in 1 1/2 cups of the sifted flours to form a stiff dough. Turn the dough out onto a lightly floured work surface and knead in about 6 tablespoons flour; the dough will be ready when it is no longer tacky and is very firm. Cover the dough and let rest 20-30 minutes.

Uncover the dough, knead it lightly and cut into 6 equal pieces. Shape each piece into a ball. Lightly cover with plastic wrap while you work with each ball of dough.

Use a rolling pin to shape each ball into a 3 1/2-inch circle; no extra flour should be necessary, but sprinkle on a bit if the dough sticks. For a nicer texture, roll the dough out another half or so inch wider and then used the palms of your hands to lightly bring in the edges of the circle and gently make it smaller again. The biscuit wrinkles up a bit on top, which improves the texture. Cover the completed dough circles with plastic wrap as you finish rolling out all the balls.

When all the balls have been rolled out, heat a large, nonstick or cast iron skillet over medium heat until drops of water hiss when flicked onto the skillet. Working in batches, place as many of the biscuits in the pan as will fit rather loosely. Cover the pan and cook over medium heat about 3 minutes, or until the bottoms are golden.

Flip the biscuits over, cover and cook until cooked through and the other sides are also golden, about 3 minutes more. A skewer inserted into the center should come out clean.

Remove the biscuits to a plate and cover with a clean tea towel. Repeat with the rest of the biscuits.